1. Field of the Invention
The present invention relates to an apparatus for the production of photoconductive components for use in electrophotography, which forms uniform photoconductive layers or resin layers on an electric conductor.
2. Description of the Prior Art
In recent years, various methods by which photoconductive components for use in electrophotography are manufactured by the use of organic photoconductive materials have been proposed, an example of which is the immersion-coating method in which an electric conductor is immersed in a coating that contains photoconductive materials, resulting in a photoconductive layer on the electric conductor.
When the conventional immersion-coating method is carried out, an overflow-apparatus by which the precipitation of the coating is prevented and in which the depth that the electric conductor is immersed in the coating is maintained at a fixed level must be used. FIG. 3 shows a conventional overflow-type apparatus for the production of photoconductive components, which comprises a coating tank 3 that is filled with a coating 7, an opening 5 through which the coating 7 is supplied to the tank 3, and an overflow receiver 6 that receives the overflowed coating from the opening 9 of the tank 3. When an electric conductor 1 is immersed in the coating 7 or is removed from the coating 7, a certain amount of coating 7 overflows, causing a turbulence in the coating 7 along the surface of the electric conductor 1 and/or a lathering of the coating 7 on the surface of the coating 7, which makes it impossible to obtain a uniformly coated film on the surface of the electric conductor 1.
To overcome this problem, the electric conductor 1 is disposed within the tank 3, first, and the coating 7 is fed to the tank and then the coating 7 is removed from the tank 3, thereby completing a coating process. However, at the time of the removal of the coating from the tank, the inside of the tank is filled with the solvent vapor of the coating, which causes damage to the coated film, resulting in a nonuniform film, and/or which causes deterioration in the film characteristics.
FIG. 4 shows another conventional apparatus for the production of photoconductive components, in which a cylindrical electric conductor 52 can move in the direction of the conductor axis with regard to a coating tank 51 that is positioned around the cylindrical conductor 52 so that the coating tank touches the surface of the cylindrical conductor 52 so as to create a water-tight system therebetween. This apparatus is disadvantages in that the surface of the cylindrical conductor 52 is scratched at the time when the cylindrical conductor 52 moves in the direction of the axis of the conductor 52 with regard to the coating tank 51 so as to coat the conductor 52 with the coating 63 that is held in the tank 51. A supporting means 53 supports the cylindrical conductor 52 thereon and is designed with the same diameter as that of the conductor and must be positioned under the conductor 52 so that the axis of the conductor 52 meets that of the supporting means 53. The cylindrical conductor 52 must move until the upper portion of the supporting means 53 is positioned within the coating tank 51 and accordingly the conductor 52 and the supporting means 53 must be smoothly connected to each other, which requires complicated and difficult techniques and/or skill in practice.